We present a model to evaluate the upper limit of the spectral efficiency of optical code-division multiple-access (OCDMA) systems with coherent sources. Phase-encoded and direct-sequence OCDMA systems are evaluated using this model. The results show that a spectral efficiency of 2.24x10^-2 b/s·Hz can be achieved with a maximum bit error rate of 10^-10 in these systems of the number of users. This result demonstrates that the maximum spectral efficiency of OCDMA systems with coherent sources is at least a factor of 5 higher than OCDMA systems with incoherent sources.
© 2005 IEEE
Martin Rochette and Leslie A. Rusch, "Spectral Efficiency of OCDMA Systems With Coherent Pulsed Sources," J. Lightwave Technol. 23, 1033- (2005)